Insect repellents

ABSTRACT

The present invention provides an insect repellent fragrance comprising; (a) at least 10% by weight of the insect repellent fragrance of geraniol; (b) at least 10% by weight of the insect repellent fragrance of diethyl phthalate; and (c) at least one or more of linalol, limonene, citronellal, terpinolene and p-tertiary butyl cyclohexyl acetate; wherein the insect repellent fragrance comprises at least 60% by total weight of the insect repellent fragrance of (a), (b) and (c). The insect repellent fragrance surprisingly demonstrates effective repellency, particularly against cockroaches, and more particularly against both German and American cockroaches.

FIELD OF THE INVENTION

[0001] The present invention relates to fragrances, particularly insectrepellent fragrances, to products comprising such fragrances and to amethod of repelling insects.

BACKGROUND OF THE INVENTION

[0002] Insects have long been known to be a nuisance to humans, and forsome insect genera, a health hazard.

[0003] Many common types of household insects such as cockroaches, e.g.American cockroaches (periplaneta americana) and German cockroaches(blattella germanica), are classified as pests and significant efforthas been made to control or eradicate them. A variety of chemicalcompounds have been discovered, e.g. N,N-diethyl-meta-toluamide, whichare efficacious in repelling cockroaches. Such chemical compounds areused in the household by applying or spraying them to surfaces of walls,floors, cabinets, containers, rugs, upholstery and carpeting, and inpotential nesting places for these insects, such as inside walls andbetween floors. Chemical compounds have been used together with hardsurface cleaners (EP-A-0619363) and wax floor polishes (U.S. Pat. No.3,018,217).

[0004] It is known in the art that essential oils and syntheticfragrance ingredients (also known as perfume materials) can repelinsects. Further, use of these ingredients may be advantageous comparedwith the use of chemical compounds in terms of presenting lower toxicityto mammals. WO 96/08147 describes an insect repellent compositioncomprising at least one active ingredient from the group of compoundsconsisting of:1,2,3a,4,5,5a,6,7,8,9,9a,9b-dodecahydro-3a,6,6,9a-tetramethylnaphtho[2,1-b] furan (AMBERLYN™); 4-(tricyclo [5.2.1.0^(2.6)] decylidene-8)butanal (DUPICAL™); 1-ethoxy-1-(2′-phenylethoxy) ethane (EFETAAL™);acetyl cedrene (LIXITONE™); and propylidene phthalide. The compositionsare described as preferably used to repel biting insects, such asmosquitoes, and in particular members of the genus Aedes.

[0005] Perfume materials, or fragrances, with repellent properties toeither American cockroaches (periplaneta americana) e.g. as disclosed inWO 00/19822 and Ngoh S. P. et al., Pestic. Sci., 1998, 54, p261, orGerman cockroaches (blattella germanica) e.g. as disclosed in JP2207004, are known. However, typically, it is difficult to formulate acomplete fragrance which effectively repels cockroaches, particularlyGerman cockroaches, and more particularly, repels both German andAmerican cockroaches, possibly together with other crawling insects e.g.ants.

SUMMARY OF THE INVENTION

[0006] In one aspect, the present invention provides an insect repellentfragrance comprising;

[0007] (a) at least 10% by weight of the insect repellent fragrance ofgeraniol;

[0008] (b) at least 10% by weight of the insect repellent fragrance ofdiethyl phthalate; and

[0009] (c) at least one or more of linalol, limonene, citronellal,terpinolene and p-tertiary butyl cyclohexyl acetate;

[0010] wherein the insect repellent fragrance comprises at least 60% bytotal weight of the insect repellent fragrance of (a), (b) and (c).

[0011] The present invention is based on the appreciation that insectrepellent fragrances of the invention surprisingly demonstrate effectiverepellency against cockroaches, particularly German cockroaches(blattella germanica), and more particularly against both German andAmerican cockroaches (blattella germanica and periplaneta americana).

[0012] By “insect repellent fragrance” as used herein is meant afragrance comprising the specified fragrance ingredients generally (butnot necessarily) having an odour that is considered pleasant orattractive, and which has an insect repellent effect. One convenientprocedure by which the insect repellent effect can be tested andmeasured involves incorporating the insect repellent fragrance into aliquid polish, with 3.0 ml of the liquid polish being evenly applied tohalf the area (i.e. 300 mm×600 mm) of a vinyl flooring test surface oftotal area 600 mm×600 mm, which is then divided into nine channels (30mm×600 mm) so that half of each channel (30 mm×600 mm) is treated andhalf is untreated, the liquid polish being allowed to dry forapproximately one hour before at least five insects are introduced intoeach channel and allowed to acclimatise to the conditions for about tenminutes, after which, i.e. at t=0 hours, the movements of the insectsare measured by video recorder. An insect repellent fragrance initially,i.e. at t=1 hour, preferably repels from the treated area at least 60%,more preferably at least 65 %, most preferably at least 70%, of theinsects.

[0013] The term “insect” as used herein is intended to encompass insectswhich typically crawl e.g. cockroaches such as German cockroaches(blattella germanica) and American cockroaches (periplaneta americana)as well as ants e.g. from the genera lasius flavus, lasius niger andmonomorium pharoanis. Preferably, fragrances in accordance with thepresent invention are used to repel cockroaches, particularly Germancockroaches and more particularly both German and American cockroaches.

[0014] Typically, the insect repellent fragrance comprises at least oneor more of linalol, limonene, citronellal, terpinolene and p-tertiarybutyl cyclohexyl acetate (PtBCHA), preferably at least two, morepreferably at least three, and even more preferably at least four ofthese fragrance ingredients. Conveniently, when present, insectrepellent fragrances as defined herein comprise at least 1% linalol, atleast 2% limonene, at least 2% and preferably greater than 3%citronellal, at least 2% and preferably greater than 3% terpinolene, andat least 3% p-tertiary butyl cyclohexyl acetate by weight of the insectrepellent fragrance.

[0015] The insect repellent fragrance may optionally be admixed withfurther excipients such as one or more further fragrance ingredients toobtain an overall pleasing fragrance with effective repellent activity,diluents, fixatives, and a further suitable solvent, or mixturesthereof.

[0016] Other excipients which may advantageously be present in theinsect repellent fragrances in accordance with the invention are:aldehyde C11 (undecylenic aldehyde); aldehyde iso C11 (GIV); allspiceoil; allyl cyclohexyl propionate; amyl salicylate; amylcinnamicaldehyde; anethole; anisic alcohol; anisic aldehyde; Applinal (Q)(Applinal is a Trade Mark); bay oil; benzyl acetate; benzyl benzoate;benzyl cinnamate; benzyl propionate; benzyl salicylate; Bourgeonal (Q)(Bourgeonal is a Trade Mark); brahmanol; camphor powder synthetic;cedarwood Virginian; cedrenol; cedryl acetate; Celestolide (IFF)(Celestolide is a Trade Mark); cineole; cinnamic alcohol; cinnamicaldehyde; cinnamon leaf oil; cinnamyl acetate; cis-3-hexenol; citral;citronella oil; citronellol; citronellyl acetate; citronellyloxyacetaldehyde; clove oil; coriander oil; coumarin; cuminic aldehyde;cyclamen aldehyde; decanal; 9-decenol; dibenzyl ether; dibutylphthalate; dihydromyrcenol; dimethyl anthranilate; dimethyl phthalate;Dimycretol (IFF) (Dimycretol is a Trade Mark); diphenyl methane;diphenyl oxide; dimethyl benzyl carbinyl acetate; dodecanol; dodecanal;elemi oil; ethyl methyl phenyl glycidate; ethyl cinnamate; EthylSafranate (Q) (Ethyl Safranate is a Trade Mark); ethyl vanillin;eugenol; evergreen oils (pine oils etc.); gamma-nonalactone;gamma-undecalactone; geranium bourbon; geranyl acetate; geranyl formate;gum benzoin; heliotropin; Hercolyn D (HER) (Hercolyn D is a Trade Mark);hexyl benzoate; hexylcinnamic aldehyde; hexyl salicylate; hydratropicaldehyde dimethyl acetal; hydroxycitronellal; hydroxycitronellaldimethyl acetal; indole; iso bornyl acetate; isopropyl myristate;iso-cyclocitral (GIV, IFF); jasmacyclene; jasmin oil; lavandin abrialis;lavender oil; Lilial (GIV) (Lilial is a Trade Mark); linalyl acetate;menthol laevo; methyl anthranilate; methyl cedryl ketone; methyldihydrojasmonate; methyl ionone; methyl myristate; methyl naphthylketone; methyl salicylate; moss treemoss; musk ketone; nerol; nerolinbromelia; neryl acetate; nonanal; oakmoss absolute; octanal olibanumresinoid; para-cresyl phenylacetate; para-methoxyacetophenone; patchoulioil; peppermint oil; petitgrain oil; 2-phenoxyethanol; phenoxyethyl isobutyrate; phenylethylacetate; phenyethyl alcohol; phenylethyl butyrate;phenylethyl phenylacetate; pimento oil; pinene, alpha; resinoid benzoinsiam; rose oil; rosemary oil; sandalwood oil; terpineol;tetrahydrolinalol; Tetrahydromuguol (IFF); thyme red; undecanal;vanillin; verbena oil; vetyvert bourbon; yara and ylang ylang.

[0017] Compounds are obtainable from the suppliers as indicated below:for those compounds labelled “(Q)”,—Quest International;“(IFF)”—International Flavours & Fragrances, Inc.; “(GIV)”—Givaudan;“(HER)”—Hercules B.V.

[0018] The insect repellent fragrance may optionally include other knowninsect repellents, and preferably known insect repellent fragranceingredients.

[0019] Suitable known insect repellents for use herein includeN,N-diethyl-m-toluamide (DEET); N,N-diethylbenzamide; citronella; Tolubalsam; Peru balsam; Eucalyptus oil; Huon pine oil; camphor; cypressoil; galbanum; dibutyl phthalate; dimethyl phthalate;1,2,3a,4,5,5a,6,7,8,9,9a,9b-dodecahydro-3a,6,6,9a-tetramethylnaphtho[2,1-b]furan; 4-(tricyclo [5.2.1.0^(2,6)]decylidene-8) butanal;1-ethoxy-1-(2′-phenylethoxy)ethane; acetyl cedrene; propylidenephthalide; citral diethyl acetal available under the trade mark“CITRATHAL”; tricyclodecenyl allyl ether available under the trade mark“FLEUROXENE”; 2-(2-methylpropyl)-4-hydroxy-4-methyltetrahydropyranavailable under the trade mark “FLOROSA”;N-methyl-N-phenyl-2-methylbutanamide available under the trade mark“GARDAMIDE”, 4-isobutyrate-3-methoxybenzaldehyde available under thetrade mark “ISOBUTAVAN”; 1-hydroxy-2-methoxy-4-propenyl benzene;2,2,7,7-tetramethyltricyclo[6.2.1.0^(1,6)]undecan-5-one available underthe trade mark “ISOLONGIFOLANONE”;7-formyl-5-isopropyl-2-methylbicyclo(2.2.2)oct-2-ene available under thetrade mark “MACEAL”; 3-methyl-5-phenylpentanal available under the trademark “MEFRANAL”; alpha iso methyl ionone; myrcenyl acetate availableunder the trade mark “NEOBERGAMATE; 10-isopropyl-2,7-dimethyloxaspiro[4.5] 3,6-decadiene available under the trade mark “NEOCASPIRENE”;tricyclo[5.2.1.0^(2,6)]dec-4-en-8-yl 2,2-dimethylpropanoate availableunder the trade mark “PIVACYCLENE”; 2-phenylethyl pivalate availableunder the trade mark “PIVAROSE” and 2,4-dimethyl-4-phenyltetrahydrofuranavailable under the trade mark “RHUBAFURAN”.

[0020] Insect repellent fragrances in accordance with the invention arepreferably incorporated in products for application to a surface e.g.floors, walls, counters, sinks, cupboards, furniture or doors etc.. Theinvention in a further aspect therefore provides a product comprising aninsect repellent fragrance in accordance with the invention.

[0021] Suitable and preferred products include for example, hard surfacecleaners, pastes and polishes e.g. furniture polish, floor polish andfloor paste in typically liquid or solid e.g. wax form. A particularlypreferred product is a floor polish.

[0022] Preferably, the products defined herein above comprise between0.01% to 20% and more preferably 0.1% to 10% by weight of the product ofan insect repellent fragrance in accordance with the present invention.

[0023] In an even further aspect, the invention provides a productcomprising an insect repellent fragrance, wherein the product comprises;

[0024] (a) at least 0.025% by weight of the product of geraniol;

[0025] (b) at least 0.025% by weight of the product of diethylphthalate; and

[0026] (c) at least one or more of linalol, limonene, citronellal,terpinolene and p-tertiary butyl cyclohexyl acetate; and

[0027] wherein the product comprises at least 0.15% by total weight ofthe product of (a), (b) and (c).

[0028] The product will typically comprise further suitable adjuvantsappropriate to the nature of the product. Suitable adjuvants may includewax e.g. paraffin, carnauba, ceresin wax etc., resins, plasticizers,water, surfactants e.g. anionic, cationic, nonionic, amphotericcompounds, builders, fluorescent brighteners, antistatic agents,antibacterial agents, fungicides, foaming agents, anti-foams, flowpromoters, suspending agents, and anti-gelling agents.

[0029] Insect repellent fragrances according to the present invention intheir simplest form as a fragrance, or as part of a product, may beapplied to a surface, including floors, furniture, walls etc. byspraying, for instance as an aerosol or by a pump action, by brushing,by wiping, for instance from an impregnated cloth or with an applicator,pouring etc. on the surface to be treated.

[0030] Thus, in an even further aspect, the invention provides a methodof repelling insects from a surface comprising the step of applying tothe surface an effective amount, typically from 0.001 to 1.000 g/m², ofan insect repellent fragrance, preferably a product comprising from0.01% to 20% by weight of the product of an insect repellent fragrance,in accordance with the present invention.

[0031] In an even further aspect the invention provides the use of aninsect repellent fragrance in accordance with the present invention forrepelling cockroaches, particularly German cockroaches (blattellagermanica) and/or American cockroaches (periplaneta americana).

[0032] The invention is illustrated by way of the following non-limitingexamples, and with reference to the accompanying drawing, in which:

[0033]FIG. 1 is a schematic representation of the arrangement of a testarea used to determine the repellency of a fragrance to insects ofinterest, the test area being divided into nine equal channels, withhalf of the total area treated with a fragrance (as shown by the spottedshading) and half untreated.

EXAMPLES

[0034] The repellency of fragrances in accordance with the presentinvention, particularly to German cockroaches (blattella germanica) andAmerican cockroaches (periplaneta americana), was demonstrated asdescribed below. For comparison, fragrances not in accordance with thepresent invention were also prepared and tested using the same protocol.

[0035] Fragrances 1 to 4 in accordance with the present invention, andcomparative fragrances 5 to 7, were prepared in the proportionsindicated in the table below. All percentages are by weight. IngredientFrag. 1 Frag. 2 Frag. 3 Frag. 4 Frag. 5 Frag. 6 Frag. 7 Citronellal 4 612 2 Geraniol 24 36 12 12 Terpinolene 4 6 12 2 Diethyl phthalate 20 1616 20 20 20 20 Benzyl acetate 5 5 5 5 6 5 5 Hexyl salicylate 5 3 3 3 3 33 Lavandin 10 10 10 6 9 6 6 Linalol 5 5 5 4 4 5 4 Methyl 3 3 5 2 2 3 2dihydrojasmonate Terpineol 5 4 6 5 5 5 5 Iso bornyl acetate 4 3 5 9 9 1112 Limonene 5 3 5 15 15 16 18 Cedarwood Virginian 1 4 5 4 5 PtBCHA 3 310 15 15 15 Diphenyl methane 2 1 5 5 5 5 Total 100 100 100 100 100 100100

[0036] The fragrances prepared were then incorporated into aself-shining liquid floor polish i.e. a floor polish which dries with ashiny finish and does not typically require buffing, the formulation ofwhich is indicated below: Ingredient % w/w Hoescht-Wachs (Hoescht) 10.20Demineralised water (boiling) 20.40 Demineralised water (roomtemperature) 63.70 Licomer A53 conc. (Hoescht) 4.50 (acrylate polymer)Bronidox L (Henkel) 0.20 (5-bromo-5-nitro-1,3 dioxane) Lutensol ON70(BASF) 0.50 (Synthetic C10 oxo-alcohol with 7 ethylene oxide units)Fragrances 1 to 7 0.50

[0037] LICOMER, BRONIDOX and LUTENSOL are all trade marks.

[0038] Each self-shining liquid floor polish comprising one offragrances 1 to 7 was tested for its ability to repel German cockroaches(blattella germanica) and American cockroaches (periplaneta americana)according to the following protocol.

[0039] Each fragrance was tested against each species of cockroach, withone species of cockroach used per test.

[0040] The test surface was vinyl flooring of 600 mm×600 mm total areawhich was divided into an arena of nine equally sized channels each of30 mm×600 mm, as illustrated in FIG. 1. 3.0 ml of a polish was appliedby syringe to the test surface and the polish distributed evenly with anapplicator such that half of the total test surface area (300 mm×600 mm)was treated with the polish, as represented by the spotted area in FIG.1, and half the total test surface area was untreated. The polish wasleft to dry for approximately one hour. Five cockroaches, periplanetaamericana or blattella germanica, of mixed age and gender were placed ineach channel and their behaviour monitored by video recorder. The videorecording commenced 10 minutes after introduction of the cockroaches tothe channels and was stopped after 1 hour of recording. The cockroacheswere then removed. After 24 hours, five cockroaches were returned toeach of the channels and the recording process repeated. The videorecording was played back and stopped at five minute intervals over anhour to obtain twelve readings. At each five minute interval, the numberof cockroaches on the treated area was counted. The repellency for thenine channels was calculated as follows:

Total number of cockroach observations possible=540 (12 times, 9channels, 5 insects per channel)

[0041] Total number of cockroach observations on treated area if noeffect=540/2=270

[0042] Total number of cockroaches observed on treated area=N (total of12 times for 9 channels)

[0043] Therefore, Repellency (%)=(270−N)/270×100

[0044] The results are as indicated in the table below with the numberrepresenting the percentage of cockroaches of a particular speciesrepelled from the treated area. Fragrance t = 1 hour t = 24 hours 1periplaneta americana 88 63 blattella germanica 94 52 2 periplanetaamericana 71 69 blattella germanica 64 68 3 periplaneta americana 84 69blattella germanica 79 86 4 periplaneta americana 85 74 blattellagermanica 72 85 5 periplaneta americana 94 87 (comparative) blattellagermanica 57 61 6 periplaneta americana 97 78 (comparative) blattellagermanica 32 58 7 periplaneta americana 81 −15 (comparative) blattellagermanica 59 2

[0045] The results show that only Fragrances 1, 2, 3 and 4 repel atleast 60% of both species of cockroach (i.e. periplaneta americana andblattella germanica) initially. Whilst comparative fragrances 5 and 6demonstrate effective repellency to cockroaches of the speciesperiplaneta americana, they demonstrate poorer repellency to theblattella germanica species. Comparative fragrance 7 does notdemonstrate effective repellency against either species of cockroachafter 24 hours.

1: An insect repellent fragrance comprising: (a) at least 10% by weightof the insect repellent fragrance of geraniol; (b) at least 10% byweight of the insect repellent fragrance of diethyl phthalate; and (c)at least one or more of linalol, limonene, citronellal, terpinolene andp-tertiary butyl cyclohexyl acetate; wherein the insect repellentfragrance comprises at least 60% by total weight of the insect repellentfragrance of (a), (b) and (c). 2: An insect repellent fragranceaccording to claim 1, wherein the fragrance comprises at least two oflinalol, limonene, citronellal, terpinolene, and p-tertiary butylcyclohexyl acetate. 3: An insect repellent fragrance according to claim1 or 2, wherein the fragrance comprises at least three of linalol,limonene, citronellal, terpinolene, and p-tertiary butyl cyclohexylacetate. 4: An insect repellent fragrance according to claim 1 or 2,wherein the fragrance comprises at least 1% by weight of the insectrepellent fragrance of linalol. 5: An insect repellent fragranceaccording to claim 1 or 2, wherein the fragrance comprises at least 2%by weight of the insect repellent fragrance of limonene. 6: An insectrepellent fragrance according to claim 1 or 2, wherein the fragrancecomprises at least 2% by weight of the insect repellent fragrance ofcitronellal. 7.: An insect repellent fragrance according to claim 1 or2, wherein the fragrance comprises at least 2% by weight of the insectrepellent fragrance of terpinolene. 8: An insect repellent fragranceaccording to claim 1 or 2, wherein the fragrance comprises at least 3%by weight of the insect repellent fragrance of p-tertiary butylcyclohexyl acetate. 9: A product comprising an insect repellentfragrance in accordance with claim
 1. 10: A product comprising an insectrepellent fragrance, wherein the product comprises: (a) at least 0.025%by weight of the product of geraniol; (b) at least 0.025% by weight ofthe product of diethyl phthalate; and (c) at least one or more oflinalol, limonene, citronellal, terpinolene and p-tertiary butylcyclohexyl acetate; wherein the product comprises at least 0.15% bytotal weight of the product of (a), (b) and (c). 11: A product accordingto claim 9 or 10, wherein the product is a hard surface cleaner, polishor paste. 12: A method of repelling insects from a surface comprisingthe step of applying to the surface an effective amount of an insectrepellent fragrance in accordance with claim 1 or
 2. 13 (canceled) 14: Amethod of repelling cockroaches which comprises subjecting saidcockroaches to an effective amount of a fragrance according to claim 1or
 2. 15: The method of claim 14 wherein the cockroaches are selectedfrom the group consisting of German cockroaches (blattella germanica)and American cockroaches (periplaneta americana).